Bernoullis Principle

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Bernoullis Principle

• The Art of Flying!

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Bernoullis Principle

• states that as the speed of a moving fluid
  increases, the pressure within the fluid
  decreases.
• Airplanes fly using the help of physics.
• Airplane wings, called Airfoils, are designed
  using Bernoullis Principle where fluids (liquid
  and air) travel faster, there is less pressure.

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Take a Closer Look!
Shape matters !
front
back
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Bernoullis Principle

• Air travels over top of wing faster, which is
  less pressure on top of the wing.
• Air travels under the wing slower, which is more
  pressure under the wing.
• The greater pressure under the wing gives it
  Lift.

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forces involved
in flight
Gravity
Less Pressure
Thrust (from engine)
AIRFOIL
Back
Front
Friction (Air resistance, drag)
Lift
Greater Pressure
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Application

• STREAMLINES
• Lines, which show air or fluid direction.
• a) CONSTRICTION - The rounding of the wing
• at the top.
• b) According to the principle, the constriction
• causes the velocity to increase, which in
  
• turn creates a low pressure area.
• c) The reverse holds as well as beneath the
• wing we have air which has low
  velocity and
• high pressure.
• d) Since THINGS LIKE LOW PRESSURE
• the wing will move up towards the
  area
• of low pressure.
• This movement upward is called LIFT.

COPY
1. Airfoil
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A better look
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Application

• Vocal cords -
• - Your lungs force air in between your
  vocal chords so
• there is less pressure between them.
• There is, therefore, greater pressure outside of
  them causing them to vibrate against each other
  producing sound.

Less Pressure
Vocal Cords
Greater Pressure
Air
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Application
Ping pong ball on hair dyer
Less Pressure

• There is less pressure in the air stream produced
  by the hairdryer because that is where the fluid
  (air) is moving faster.
• There is more pressure, therefore, outside the
  air stream causing the ping pong ball to STAY in
  the air stream.

Greater pressure
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Application
Curveball
NO SPIN
SPIN
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Application
Fan